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931Owner · Joined: 14 Feb 2009 Posts: 352 Location: Chicago NW Suburbs

I've been reading up about inter-cooler mods for the 931 but the biggest common drawback I've noticed is you have to do major body work for the piping.

I have an old F150 which you can get front mount pusher fans if you're planning to get extra HP and get rid of the belt driven radiator fan.

When I got the fan assembly off the 931 I noticed all this room there. What would happen if the std fans were changed for low profile pusher type fans up front of the radiator? This would give loads of room for a fairly decent size intercooler and you wouldn't need to modify the body too bad for routing the pipes.

This is just a passing thought.
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1980 Turbo
-too many cars and too many motobikes

Shurick · Joined: 15 May 2005 Posts: 524 Location: Russia, Moscow.

Going this way right now. Can't see any drawbacks instead of a bit tight plumbing.
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WBR, Shurick
'79 931 -- intercooled K26-3060-6.10 turbo @ 1.2 bar, EFI+EDIS, 951S brakes, stripped interior, 951 look.
'86 924S -- R.I.P.
https://www.instagram.com/ru_pacecar/

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

The biggest drawback is that the intercooler will be getting warmer air which has been heated by the radiator. Mounting in front of the radiator is more efficient.

Dennis
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81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black

931Owner · Joined: 14 Feb 2009 Posts: 352 Location: Chicago NW Suburbs

SWEET! I was surprised no one had thought of it before.

Let us know how it turns out.
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1980 Turbo
-too many cars and too many motobikes

Shurick · Joined: 15 May 2005 Posts: 524 Location: Russia, Moscow.

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

931Owner · Joined: 14 Feb 2009 Posts: 352 Location: Chicago NW Suburbs

The only other concern I see is a hot spot where the motor for the fans will be since they will block cooling but the space is negligible considering the area of the radiator.
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1980 Turbo
-too many cars and too many motobikes

peterld · Posted: Sat Apr 03, 2010 10:28 pm Post subject:

My racecar has had a very large FMIC in front of the original radiator for nigh on ten years with no overheating problems. And this is in a climate similar to that of southern Florida! Original fan, and A/C fan rejigged to work in tandem with normal fan, take care of any heat.
Always thought I might need to go for a custom water radiator but never eventuated.

What body work for the piping? Other than one small notch in the top panel side to relieve rubbing, the sheet metal is as it left the factory. Gigantic windscreen washer bottle has been dispensed with and a small bottle mounted lower in the body. Yes clearances are tight, but it all fits beautifully.
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80/81 932/8 ROW

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

I applaud the creative thinking...however, putting the intercooler behind the rad is a BAD idea for the reason noted above. Don't do it.

The pusher fan setup you describe on the truck is not a good comparison. It might be more efficient than the belt driven fan, but a pusher fan will never be as efficient at cooling as a puller because it will block ambient flow TO the heat exchanger, especially when the fans aren't running. Rad fans really need to be shrouded for optimal effectiveness.

You would be much better served to find a modern, low profile, properly shrouded dual fan setup to put behind the rad. There is plenty of room in front of the rad for an intercooler, you just have to get a little creative with the plumbing.

You can also improve the overall cooling efficiency of your car if you remove the A/C condenser (provided you don't care about A/C).
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erstwhile owner of just about every 924 variant ever made